Getting diagnosed with endometriosis typically involves a combination of symptom evaluation, physical examination, imaging, and sometimes surgery. The process is notoriously slow: the average time from first symptoms to a confirmed diagnosis is 7.5 to 10 years. Understanding what each step involves, and how to prepare for it, can help you move through the process faster.
Why Diagnosis Takes So Long
Endometriosis symptoms overlap significantly with other conditions like irritable bowel syndrome, urinary tract infections, ovarian cysts, and adenomyosis. Painful periods, pelvic pain, and digestive issues are common enough that they’re often attributed to something else first. Many people are told their pain is normal or dismissed entirely before a clinician considers endometriosis. In the UK, the average diagnostic delay has actually worsened over time, climbing from 7.5 years in 2020 to roughly 10 years in more recent estimates.
Symptoms That Point Toward Endometriosis
Certain symptom patterns raise the likelihood of endometriosis considerably. Severe period pain is the most common, affecting 97% of people with confirmed disease compared to about 74% of those without it. But endometriosis pain extends well beyond periods. About 47% of people with the condition report chronic pelvic pain outside of menstruation, compared to 21% of those without it. Pain during sex affects roughly 59% of people with endometriosis versus 28% of controls.
Two symptoms are especially distinctive. Painful urination occurs in about 32% of people with endometriosis but only 4% of those without it. Painful bowel movements affect 47% versus 15%. If you experience several of these together, particularly in a cyclical pattern that worsens around your period, that combination is highly suggestive of endometriosis.
Other symptoms clinicians look for include fatigue, infertility, lower back pain, pain radiating to the legs, shoulder tip pain, and in rare cases cyclical coughing or chest pain (which can indicate endometrial tissue in the lungs).
What Happens at Your Appointment
The first step is a detailed conversation about your symptoms. A clinician will ask about the timing, location, and severity of your pain, whether it’s cyclical, and how it affects daily life. They’ll also ask about your menstrual history, bowel and bladder function, and any difficulty getting pregnant.
A pelvic exam may follow, where the clinician feels for deep nodules or cysts. This exam can sometimes detect endometriomas (cysts on the ovaries) or deep nodules behind the uterus, but its diagnostic accuracy is low. A normal pelvic exam does not rule out endometriosis, and guidelines are clear that further testing should still happen even when the exam finds nothing.
Imaging: Ultrasound and MRI
If endometriosis is suspected, the next step is imaging, usually a transvaginal ultrasound. This is the most accessible and widely used tool. For detecting endometriosis on the bowel (rectosigmoid area), ultrasound picks up 79 to 94% of cases depending on the study and the operator’s experience. For ovarian endometriomas, it performs well. Where it struggles is with smaller or more diffuse lesions, particularly on ligaments behind the uterus, where sensitivity drops as low as 25% in some studies.
MRI is generally more accurate for mapping deeper disease. For ligament involvement, MRI sensitivity ranges from 75 to 94%, compared to the highly variable 25 to 83% for ultrasound. For lesions in the rectovaginal septum (the tissue between the vagina and rectum), MRI detects 83 to 88% versus 67 to 73% for ultrasound. MRI is particularly useful when surgery is being planned, because it helps surgeons understand where disease is located before they operate.
One critical point: a clean ultrasound or MRI does not mean you don’t have endometriosis. Superficial endometriosis, the kind that sits on the surface of the pelvic lining, is essentially invisible to both imaging methods. Current guidelines emphasize that negative imaging should not end the diagnostic workup if symptoms are suggestive.
No Blood Test Can Confirm It
There is currently no reliable blood test, urine test, or biomarker that can diagnose endometriosis. European guidelines specifically recommend against using biomarkers from blood, menstrual fluid, or endometrial tissue for diagnosis. Researchers are exploring saliva-based tests that analyze tiny RNA molecules, and early results from a study of 200 participants showed promise, but these tests still need external validation before they become clinically available.
Surgical Diagnosis Through Laparoscopy
When imaging is negative but symptoms persist, or when initial treatments haven’t worked, laparoscopy is the next step. This is a minimally invasive surgery where a small camera is inserted through a cut near the navel, allowing the surgeon to directly see endometrial-like tissue growing outside the uterus.
Laparoscopy has long been considered the gold standard for diagnosis, but visual identification alone has limitations. Surgeons correctly identify endometriosis by sight about 90% of the time when it’s actually there, but they also call it endometriosis when it isn’t about 60% of the time. For this reason, guidelines recommend taking a tissue sample (biopsy) during surgery and sending it to a pathologist for confirmation. In validation studies, surgeons visually diagnosed endometriosis in 82% of patients, while pathology confirmed it in 74%, highlighting that what looks like endometriosis isn’t always endometriosis under a microscope.
During laparoscopy, the surgeon can also treat the disease by removing or destroying visible lesions, making it both a diagnostic and therapeutic procedure.
How Endometriosis Is Staged
If endometriosis is confirmed at surgery, it’s assigned a stage from I to IV based on a point system. Points are tallied based on the size and depth of lesions on the ovaries and pelvic lining, and the severity of any adhesions (scar tissue binding organs together). Stage I (1 to 5 points) is minimal disease. Stage II (6 to 15 points) is mild. Stage III (16 to 40 points) is moderate. Stage IV (over 40 points) is severe. A single finding of complete obliteration of the space behind the uterus automatically scores 40 points, placing it in the severe category.
Staging does not always correlate with pain. Someone with Stage I can have debilitating symptoms, while someone with Stage IV may have relatively little pain. The staging system is more useful for describing the physical extent of the disease, particularly when planning treatment or assessing fertility.
Choosing the Right Specialist
Who performs your evaluation matters. Surgeons with fellowship training in minimally invasive gynecologic surgery (MIGS) diagnose deep endometriosis during surgery at significantly higher rates than general OB-GYNs: 66% of cases versus 48%. They’re also far more likely to take tissue samples for pathology confirmation. In one study, MIGS-trained surgeons sent non-ovarian specimens to pathology in 62% of cases, compared to just 2% for general OB-GYNs. If you suspect endometriosis and your initial evaluations haven’t been productive, seeking out a specialist with specific endometriosis expertise can make a real difference.
How to Prepare for a Faster Diagnosis
Tracking your symptoms before your appointment gives your clinician significantly more to work with than a verbal description from memory. Smartphone apps designed for endometriosis (like Phendo) let you log pain location, severity, and type daily, along with gastrointestinal symptoms, urinary issues, and mood. Tracking by body location is especially useful because it helps distinguish endometriosis-related pain from symptoms of overlapping conditions like IBS.
At minimum, keep a record of your pain across two to three full menstrual cycles. Note when pain occurs relative to your period, where it’s located, how severe it is on a 1-to-10 scale, and whether it comes with bowel or bladder symptoms. Record how pain affects your ability to work, exercise, sleep, or have sex. This kind of data mirrors what researchers use in clinical studies and gives your clinician a much clearer picture than a single office visit can provide.
If you’ve already been evaluated for other conditions like IBS, ovarian cysts, or urinary infections without finding an explanation for your symptoms, bring those results. A history of negative workups for other causes, combined with a pattern of cyclical pain and multiple symptom types, builds a strong case for pursuing endometriosis-specific evaluation.